Haskell extraction: use explicit -XMagicHash instead of -fglasgow-exts
Haskell extraction: use explicit -XMagicHash instead of -fglasgow-exts

When Coq's Haskell extraction needs to use unsafeCoerce, it passes
the -fglasgow-exts option to GHC, but recent versions of GHC warn
against this:

  xx.hs:1:16: Warning:
      -fglasgow-exts is deprecated: Use individual extensions instead

This patch does as the warning suggests, replacing -fglasgow-exts
with the specific option that the extraction needs (-XMagicHash).

ppedrot/coq,Zimmi48/coq,amintimany/coq,asr/coq,Matafou/coq,TOSPIO/coq,SkySkimmer/coq,TheTypoMaster/coq,TOSPIO/coq,gares/coq,Zimmi48/coq,gares/coq,TOSPIO/coq,william-lawvere/coq,amintimany/coq,jpdeplaix/coq,mattam82/coq,JasonGross/coq,coq/coq,8l/coq,Matafou/coq,maximedenes/coq,coq/coq,shindere/coq,william-lawvere/coq,barras/coq,ejgallego/coq,Lionel-Rieg/coq,ejgallego/coq,jpdeplaix/coq,gmalecha/coq,aspiwack/coq,maximedenes/coq,herbelin/github-coq,mattam82/coq,asr/coq,gares/coq,pirapira/coq2rust,barras/coq,letouzey/coq-wip,mlasson/coq,JasonGross/coq,barras/coq,ppedrot/coq,pirapira/coq2rust,shindere/coq,gares/coq,mattam82/coq,letouzey/coq-wip,JasonGross/coq,ppedrot/coq,ale-f/coq,8l/coq,gmalecha/coq,ale-f/coq,jpdeplaix/coq,SkySkimmer/coq,gares/coq,Ptival/coq,letouzey/coq-wip,maximedenes/coq,ale-f/coq,gmalecha/coq,SkySkimmer/coq,ejgallego/coq,amintimany/coq,coq/coq,silene/coq,ppedrot/coq,Matafou/coq,herbelin/github-coq,aspiwack/coq,silene/coq,ejgallego/coq,8l/coq,letouzey/coq-wip,william-lawvere/coq,letouzey/coq-wip,mlasson/coq,ppedrot/coq,maximedenes/coq,maximedenes/coq,Zimmi48/coq,coq/coq,mlasson/coq,Ptival/coq,TheTypoMaster/coq,TheTypoMaster/coq,SkySkimmer/coq,Lionel-Rieg/coq,asr/coq,JasonGross/coq,silene/coq,Zimmi48/coq,Ptival/coq,herbelin/github-coq,Lionel-Rieg/coq,pirapira/coq2rust,shindere/coq,aspiwack/coq